It is increasingly important to determine the location of wireless devices, such as smart phones, tablet computers, automobile computers, and the like. Some wireless location positioning systems work on the principle of comparing (i) cached received signal strength indicator (RSSI) values of wireless data frames transmitted from the wireless device with (ii) cached fingerprints of the RSSI values.
However, the traditional algorithms to determine the location of wireless devices are based on omnidirectional transmissions from the respective wireless devices. With the adoption of beamforming capable chipsets, wireless devices are capable of transmitting data frames in a directional beam at a higher signal strength than a traditional omnidirectional wireless transmission. Thus, wireless devices capable of beamforming transmissions exhibit a bias in the sensor observations as compared to the cached fingerprints, and the location-tracking accuracy consequently decreases.
Accordingly, there is a need for methods and systems for mitigating the impact of beamforming on the accuracy of Wi-Fi based location tracking of client devices.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.